The aim of this research program is to understand the basic brain mechanisms which govern fundamental adaptive behaviors of animals, and the present focus is to study how the medial hypothalamus participates in body energy balance regulation. Specifically, our working model, based on completed work, is that the medial hypothalamus is crucial to body energy regulation by its elaboration of both excitatory and inhibitory control of feeding in response to body nutrient depletion and repletion. The present grant year is devoted to ascertaining how medial hypothalamic damage changes animals' regulatory responsivity to major nutritional challenges administered in the context of its ongoing feeding cycle. Further, we are testing the hypothesis that these regulatory functions are the direct consequence of local metabolism of nutrients within the medical hypothalamus. It has already been demonstrated that this part of the brain stores nutrients for longer periods than the rest of the brain, and attempts are being made to understand the anatomy and metabolism of this storage process and to correlate it with ongoing feeding.